Commutator-cylinder for dynamo-electric machines



N. W. STORER.

COMMUTATOR CYLINDER FOR DYNAMO ELECTRIC MACHINES.

APPLICATION FILED SEPT.2I, ms.

1,326,303. Patented Dec. 30,1919.

7 INVENJTOR Narman W JfOIQII fift 14' a BY WITNESSES UNITED STATES PATENT onnion.

NORMAN W. STORER, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR 'IO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

COMMUTATOR-CY'LINDER FOR DYNAMO-ELECTRIC MACHINES.

Specification of Letters Patent.

Patented Dec. 30, 1919.

Application filed September 27, 1916. Serial No. 122,445.

To all whom it may concern:

Be it known that I, NORMAN IV. Sironma, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Commutator-Cylinders for Dynamo-Electric Machines of which the following is a specification.

My invention relates to the construction of commutator cylinders for dynamo-electric machines, and it has for its object to provide a commutator cylinder that is particularly adapted for use in connection with dynamoelectric machines of the high-voltage type.

In the construction of commutator cylinders for high voltages, it is essential that sufficient insulation be provided in order to prevent electrical discharges between the conducting segments which are at machine potential and the V rings which are at ground potential. The obvious expedient is to increase the length of the creepage path, which is usually defined as the shortest distance over the exposed surfaces of the insulating material between the live parts and the gromid. -The desired results have heretofore been obtained by merely extending the insulation beyond the conducting segments, but, owing to the space limitations existing in certain types of apparatus, such as railway motors, this has not always been found practicable.

According to the present invention, I pro vide a high voltage commutator cylinder having a safe creepage path without materially increasing the length of the commutator cylinder. Furthermore, the additional insulating material required by the practice of my invention may be readily applied to commutator cylinders of the existing type without serious modification of their structure.

The single figure of the accompanying drawing is a view, partially in section and partially in side elevation, of a portion of a commutator cylinder embodying my invention.

A plurality of conducting and insulating segments 1 and 2, respectively, are alternately disposed upon a metal V-ring 3 that is adapted to coact with a similar V-ring (not shown) and the bolts 4 to maintain the segments in their proper relation. The V- of the segments 1 and 2.

ring 3 is mounted upon a sleeve 5 that is carried by a rotatable shaft 6 and is suitably positioned thereon by a nut 7. A layer 8 of insulation (preferably mica), conforming to the outer surface of the V-ring 8, is interposed between the segments 1 and 2 and the V-ring and projects beyond the ends The V-ring 3 is provided with an annular extension 3 which serves as a partial support for the project-- ing portion of the insulation 8 which is surrounded and protected from in ury by a sleeve 9 of hard and durable insulating material.

A ringlO preferably composed of a hard and durable insulating material, such as bakelite, is formed with its inside and outside diameters corresponding to those of the annular extension3. A' pressed metal retaining ring 11, )rovided atone end with a flared-out portion 12, is so proportioned that it will have a close pressed fit with the inner surface of the extension 3' and the ring 10, the flared-out portion 12 serving to hold the ring 10 in engagement with the end of the i-ring 3. The ring 10 is pro vided with an outwardly extending flange 13 that fits closely against the end of the extended portion of the insulation 8 and the sleeve 9.

From the foregoing, it is apparent that the length of the creepage path provided by the exposed surfaces of the sleeve 9 and of the insulating ring 10 is several times L which represents the length of the creepage path provided by merely extending the V- ring and the insulation 8 beyond the conducting segments. It is also apparent that my invention may be readily applied to commutator cylinders of the above described type by applying the insulating and retaining rings together with suitable insulating material between the ends of the conducting segments and the flange of the insulatmg ring.

While I have shown my invention in its simplest and preferred form, it is not so limited but is susceptible of various minor changes and modifications as indicated in the appended claims.

I claim as my invention:

1. In a commutator cylinder, the combination with conducting and insulating segments and a supporting V-ring therefor having a portion projecting beyond the ends insulating of said segments, of a separate V-ring and member abutting the end of said in alinement therewith.

In a commutator cylinder, the combination with conducting and insulating segments and supporting V-ring therefor having a portion projecting beyond. the ends of said segments, of an insulating member abutting the end of said V-ring and having a portion thereof projecting laterally beyond the surface of said ii-ring.

In a commutator cylinder, the combination with conducting and insulating segments and a supporting V-ring therefor having a portion projecting beyond the ends of said segments, of a separate insulating ring located at the end of said V-ring and a retaining ring coacting with said V-ring for maintaining said insulating ring in engagement with said. V-ring.

i. In a commutator cylinder, the combination with a ii-ring, and an insulating ring located adjacent thereto and having the same inside diameter, of a retaining ring having its outer surface coacting with the inner surfaces of said rings for maintaining the said rings in alinement.

5. In a comi iutator cylinder, the combi nation with a \/ring and an insulating ring located adjacent thereto, of a retaining ring coacting with said V-ring to maintain the said rings in alinement.

- 6. In a commutator cylinder, the combination with a V-ring and an insulating ring located ad acent thereto, of a retaining ring having a pressed fit within said V-ring for maintaining said rings in alinement.

7. In a commutator cylinder, the combination with a V-ring and an insulating ring located adjacent thereto and having the sameinside diameter, of a retaining ring having a pressed it within the said rings for maintaining said rings in alinement.

8. In a commutator cylinder, the combination with conducting and insulating segments and a supporting V-ring therefor having a portion projecting beyond the ends of said segments, of an annular insulating member of substantially an- L-shape cross section abutting the end of said V-ring, one portion thereof projecting laterally beyond the surface of said V-ring.

9. In a commutator cylinder, the combination with conducting and insulating segments and a supporting ll-ring therefor having a portion projecting beyond the ends of said segments, of an. annular insulating member abut" g the end of said V-ring, one portion of which is of like diameter with the V-ring and the other portion of which is of greater diameter than said V-ring.

10. In a commutator cylinder, the combination with conducting and insulating seg ments and a supporting V-ring therefor having a portion projecting beyond the ends of said segments, of an annular insulating member abutting the end of said V-ring, one portion of said insulating ring being of substantially the same cross-section as the adjacent end portion of said v ring', and another portion of said insulating ring projecting laterally beyond. the surface of said V-ring.

In testimony whereof I have hereunto subscribed my name this 25th day of Sept,

NORMAN IV. STORER. 

